From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,dbcfe2b0a74da57e X-Google-Attributes: gid103376,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news1.google.com!news.glorb.com!newscon02.news.prodigy.net!prodigy.net!newsfeed-00.mathworks.com!nntp.TheWorld.com!not-for-mail From: Robert A Duff Newsgroups: comp.lang.ada Subject: Re: Inherited Methods and such Date: Thu, 27 Sep 2007 09:39:46 -0400 Organization: The World Public Access UNIX, Brookline, MA Message-ID: References: <1190239986.762473.204290@k79g2000hse.googlegroups.com> <1rw45b3rmvmcr$.1df4wst5oknbl$.dlg@40tude.net> <1190296353.624737.150940@y42g2000hsy.googlegroups.com> <11m13st1f92kf$.m8s6y8mc8ebk.dlg@40tude.net> <1190321119.206313.65290@57g2000hsv.googlegroups.com> <1190408526.100291.265040@50g2000hsm.googlegroups.com> <9ukf2wtqjs0q$.iuijmal4x56b$.dlg@40tude.net> <1190497995.498679.119190@19g2000hsx.googlegroups.com> <1mw3qju08q8uj.sgzht7ld9ydc$.dlg@40tude.net> <1190579805.451187.71140@d55g2000hsg.googlegroups.com> <1i8ksr774bjbj.vpmnx3c0i9qz.dlg@40tude.net> <1190646125.024072.310020@19g2000hsx.googlegroups.com> <1r9s9v6pcjifl.vp4ktk0unpd1.dlg@40tude.net> <1190753631.240548.101820@19g2000hsx.googlegroups.com> <1190843408.713838.128690@g4g2000hsf.googlegroups.com> NNTP-Posting-Host: shell01.theworld.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: pcls6.std.com 1190900386 12072 192.74.137.71 (27 Sep 2007 13:39:46 GMT) X-Complaints-To: abuse@TheWorld.com NNTP-Posting-Date: Thu, 27 Sep 2007 13:39:46 +0000 (UTC) User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/21.3 (irix) Cancel-Lock: sha1:SYFCdQDhWwPH8OXZjSNiL2jMQA8= Xref: g2news2.google.com comp.lang.ada:2159 Date: 2007-09-27T09:39:46-04:00 List-Id: Maciej Sobczak writes: > My claim in this lengthy and philosophical discussion is that C++ > provides a complete solution which can be shortly described like this: > the final type is not established from the very beginning, but is > progressively moving along the inheritance chain as the subsequent > constructors of base types complete their work. Thank's to this, > primitive operations never dispatch further than what can be > statically reasoned about. Thanks for summarizing the discussion for me! I agree with you that during construction you shouldn't dispatch to the deeper type(s) -- i.e. the ones that can see parts of the object that are not yet initialized. But I find the C++ solution less than ideal -- the programmer might well expect to dispatch to the deeper type, and be surprised when it doesn't. Question: why do you want to dispatch at all during construction? I think I remember you saying you wanted to install the object in some global data structure. But that just means you want to create an access-to-class-wide, and put that somewhere -- no need to dispatch. In other words, would you be happy with a rule saying you can't dispatch during construction? (Never mind, for the moment, whether that's a compile-time or run-time rule (or some of both).) If the answer is "no", please give a realistic example where dispatching during construction makes sense. (I apologize if you already did -- as I said, I got lost in this thread, and I didn't read all of it.) - Bob